Spontaneous organization of the cortical structure through endogenous neural firing and gap junction transmission.

We explore the effects of gap junctions, direct neural transmission between adjacent cells, on activity-dependent network formation. It is found that endogenous neural activities and weak firing correlations via gap junctions can regulate elaborately both the topographic structure in vertical connections and the radial structure in horizontal connections. Provided that pre-establishment of the lateral connection structure is required for the postnatal cortical map organization and genetic factors cannot perform such detailed regulation of synaptic connections, neural interactions via gap junctions could play an indispensable role in the brain development.